Table 1.
Basic description of appendicitis admissions, pollutant concentrations and meteorological factors in Linfen, China, 2016–2018.
| Variables | Sum | Mean (SD) | Min | P10 | P25 | P75 | P90 | Max |
|---|---|---|---|---|---|---|---|---|
| Appendicitis cases | 1,427 | 1.30 (0.95) | 0 | 0 | 1 | 2 | 3 | 5 |
| Male | 1,183 | 1.08 (0.96) | 0 | 0 | 0 | 2 | 2 | 5 |
| Female | 244 | 0.22 (0.47) | 0 | 0 | 0 | 0 | 1 | 3 |
| ≤ 20 years | 174 | 0.15 (0.38) | 0 | 0 | 0 | 0 | 1 | 2 |
| 21–39 years | 1,110 | 1.01 (0.98) | 0 | 0 | 0 | 2 | 2 | 5 |
| ≥40 years | 143 | 0.13 (0.35) | 0 | 0 | 0 | 0 | 1 | 3 |
| Warm season (April to September) | 492 | 0.45 (0.65) | 0 | 0 | 0 | 1 | 1 | 4 |
| Cold season (October to March) | 935 | 0.85 (1.11) | 0 | 0 | 0 | 2 | 2 | 5 |
| PM10 (μg/m3) | - | 117.42 (77.82) | 16 | 49.5 | 68 | 138 | 208 | 658 |
| SO2 (μg/m3) | - | 67.62 (95.21) | 4 | 13 | 19 | 67 | 154 | 858 |
| NO2 (μg/m3) | - | 36.04 (18.38) | 6 | 16 | 23 | 45 | 62 | 124 |
| Mean temperature (°C) | - | 14.87 (10.50) | −10.0 | 0.3 | 5.6 | 24.0 | 28.6 | 33.3 |
| Relative humidity (%) | - | 52.58 (17.79) | 10.0 | 29.0 | 39.0 | 65.0 | 77.0 | 98.0 |
SD, standard deviation; P10, P25, P75, P90, the10th, 25th, 75th, 90th percentile; PM10, Particulate matter with aerodynamic diameter ≤ 10 μm; NO2, Nitrogen dioxide; SO2; Sulfur dioxide.